what did he discover

• Being in a rural area, there were a lot of dairy farms. By chance, Jenner was often called out to treat dairy maids who were

  suffering from ‘cowpox’. Cowpox caused red blisters on the skin, similar to smallpox and it could be transmuted from cows to

  humans easily.
• Jenner was interested in how similar the two diseases were. He also noticed another important connection - the milk maids who had previously caught cowpox, never caught smallpox, even during an epidemic. To Jenner, this meant that

  whatever was in the cowpox disease was helping to prevent smallpox.
• In 1796 he deliberately infected a local boy, James Phipps with cowpox.

  Six weeks later, he attempted to infect James with smallpox. As he suspected, James did not catch Smallpox at

  all.
• To test his theory further, Jenner went on to infect more local people with cowpox to further to gain more evidence. Jenner was able to report his successful findings by 1798. However, there was so much outrage at his work that the Royal Society refused to print his work.
• So he published it himself by raising the money himself. He called it ‘An

  Enquiry into the Causes and Effects of the Variola Vaccinae.’ He called the technique he had used ‘vaccination’ after the Latin word for cow, vacca.
• Jenner made sure the instructions and methods he wrote down for this were detailed but easy for

  other doctors to follow. Jenner used strict scientific methods which involved careful

  observation and testing in his work.